Based on an analysis of data from the 2008 Health and Nutrition Barometer, this article examines the specific characteristics of eating behaviors among 12- to 30-year-olds compared to those of adults, as well as the factors associated with them. This stage of life represents a transition between childhood and adult eating patterns and is characterized by gender differences and certain social inequalities. The gap between nutritional knowledge and eating behaviors, along with the incorporation of socially differentiated norms, calls on public authorities to adopt health promotion strategies based on both individual and environmental factors. [author’s abstract]